東京卍リベンジャーズ

Takemichi Hanagaki, a 26-year-old going nowhere, learns that his middle-school girlfriend Hinata Tachibana has been killed by the Tokyo Manji Gang. Shoved in front of a train, he wakes twelve years in the past as his teenage self, and discovers that shaking hands with Hinata's brother Naoto lets him jump between past and present. To save her, Takemichi works his way into the Tokyo Manji Gang to change the events that set its violent future in motion.